#555FAB
Closest named color: French Blue (#436BAD). oklch(51.4% 0.12 275.7), rgb(85, 95, 171).
Aa
White text reads best on this color (5.81:1).
About this color
#555FAB is a medium-dark, moderately saturated blue. In OKLCH its lightness is 51%, its chroma 0.120 and its hue 276°. Its hue sits on the cool side of the wheel. The nearest named color is French Blue (#436BAD), ΔE 0.036 away. White text reads best on it, at 5.81:1.
| Hue family | Blues |
| Lightness | medium-dark (51%) |
| Chroma | moderately saturated (0.120) |
| Temperature | cool |
| Nearest name | French Blue (#436BAD) |
| Black text | 3.61:1 |
| White text | 5.81:1 |
Values
| HEX | #555FAB |
| RGB | rgb(85, 95, 171) |
| HSL | hsl(233, 34%, 50%) |
| OKLCH | oklch(51.4% 0.12 275.7) |
Contrast
WCAG 2 contrast ratios are the conformance target: AA needs 4.5:1 for body text and 3:1 for large text, AAA needs 7:1. APCA Lc values are supplementary guidance from the WCAG 3 drafts.
| Pair | WCAG 2 | Result | APCA | APCA guidance |
|---|---|---|---|---|
| White text on #555FAB | 5.81:1 | AA | Lc -84.2 | Fine for body text |
| Black text on #555FAB | 3.61:1 | AA large text | Lc 25.1 | Dividers and decoration only |
| #555FAB text on white | 5.81:1 | AA | Lc 78.9 | Fine for body text |
| #555FAB text on black | 3.61:1 | AA large text | Lc -22.9 | Dividers and decoration only |
Tints and shades
A 50–950 scale built in OKLCH: the hue is held, lightness follows a Tailwind v4-like curve, and every step is kept inside the sRGB gamut. This color sits at step 700.
-
Step 50
50
#F4F5FB
oklch(97.1% 0.008 278.6)
-
Step 100
100
#E6E9F5
oklch(93.5% 0.016 274.8)
-
Step 200
200
#D3D8EF
oklch(88.5% 0.032 276)
-
Step 300
300
#B6BEE7
oklch(80.9% 0.059 276.4)
-
Step 400
400
#909CDB
oklch(70.7% 0.093 275.5)
-
Step 500
500
#7682D1
oklch(63.1% 0.119 275.9)
-
Step 600
600
#5F6ABE
oklch(55.5% 0.13 275.7)
-
Step 700
700 (this color)
#555FAB
oklch(51.4% 0.12 275.7)
-
Step 800
800
#414885
oklch(42.7% 0.101 276.3)
-
Step 900
900
#363D6A
oklch(37.6% 0.077 275.4)
-
Step 950
950
#20243E
oklch(27% 0.049 276)
#555FAB with color blindness
Simulated with the Machado et al. (2009) model. ΔE is how far the color moves: below about 0.02 you would not notice a change.
| Vision | Seen as | Shift (ΔE) |
|---|---|---|
| Protanopia (no red cones) | #4069AE | 0.034 |
| Deuteranopia (no green cones) | #3862A9 | 0.035 |
| Tritanopia (no blue cones) | #326F7C | 0.107 |
| Achromatopsia (no color) | #656565 | 0.120 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #555FAB
#555FAB
oklch(51.4% 0.12 275.7)
- #7A6600
#7A6600
oklch(51.4% 0.106 95.5)
Analogous
Neighbouring hues, 30° either side.
Split complementary
The two hues beside the complement (150° and 210°).
Triadic
Three hues spaced 120° apart.
Palettes with this color
Curated palettes that contain a color within ΔE 0.04 (OKLab) of #555FAB, closest first.
No curated palette has a color within ΔE 0.04 of #555FAB.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- French Blue #436BAD ΔE 0.036
- Dusky Blue #475F94 ΔE 0.043
- Iris #6258C4 ΔE 0.049
- Mid Blue #276AB3 ΔE 0.051
- Denim Blue #3B5B92 ΔE 0.055
- Flat Blue #3C73A8 ΔE 0.060
- Twilight #4E518B ΔE 0.061
- Muted Blue #3B719F ΔE 0.063
Use #555FAB in your product
Turn it into light and dark UI roles checked for contrast, then export to Tailwind v4, shadcn/ui, CSS or design tokens.